Question

For incoming freshman at BYU, ACT scores are Normally distributed with a mean of 28 and a standard deviation of 2. How many standard deviations away from the mean is an ACT score of 31?

Answer 1

To calculate how many standard deviations away from the mean an ACT score of 31 is, we need to use the formula:

z = (x - μ) / σ

Where:

x = ACT score of 31

μ = mean of ACT scores (28)

σ = standard deviation of ACT scores (2)

z = number of standard deviations away from the mean

Substituting the values, we get:

z = (31 - 28) / 2

z = 1.5

Therefore, an ACT score of 31 is 1.5 standard deviations away from the mean.